1. Field of the Invention
This invention relates to a method of manufacturing transformer windings embedded in casting resin and more particularly to a method of manufacturing a transformer coil encapsulated in casting resin utilizing a disposable casting mold wherein the disposable mold acts both as a winding mandrel and as an inner mold shell for resin encapsulation. The invention is particularly suited to the manufacture of non-standard oval shaped or circular shaped epoxy encapsulated coils for dry type distribution transformers.
2. Description of the Prior Art
Currently the state of the art is precision made standard sized re-usable round shaped mandrels and molds in fixed size increments with costly tap inserts. Examples of prior art methods of encapsulating transformer coils are disclosed in U.S. Pat. Nos. 4,337,219, 4,540,536, 5,036,580 and 5,633,019.